<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>菜鸟教程</title>
    <style>
      #myInput {
        background-image: url("https://static.runoob.com/images/mix/searchicon.png"); /* 搜索按钮 */
        background-position: 10px 12px; /* 定位搜索按钮 */
        background-repeat: no-repeat; /* 不重复图片*/
        width: 100%;
        font-size: 16px; /* 加大字体 */
        padding: 12px 20px 12px 40px;
        border: 1px solid #ddd;
        margin-bottom: 12px;
      }

      #myUL {
        /* 移除默认的列表样式 */
        list-style-type: none;
        padding: 0;
        margin: 0;
      }

      #myUL li a {
        border: 1px solid #ddd; /* 链接添加边框 */
        margin-top: -1px;
        background-color: #f6f6f6;
        padding: 12px;
        text-decoration: none;
        font-size: 18px;
        color: black;
        display: block;
      }

      #myUL li a.header {
        background-color: #e2e2e2;
        cursor: default;
      }

      #myUL li a:hover:not(.header) {
        background-color: #eee;
      }
    </style>
  </head>

  <body>
    <input
      type="text"
      id="myInput"
      onkeyup="myFunction()"
      placeholder="搜索..."
    />

    <ul id="myUL">
      <li><a href="#" class="header">A</a></li>
      <li><a href="#">Adele</a></li>
      <li><a href="#">Agnes</a></li>

      <li><a href="#" class="header">B</a></li>
      <li><a href="#">Billy</a></li>
      <li><a href="#">Bob</a></li>

      <li><a href="#" class="header">C</a></li>
      <li><a href="#">Calvin</a></li>
      <li><a href="#">Christina</a></li>
      <li><a href="#">Cindy</a></li>
    </ul>
  </body>
</html>
